Total Equity and Other Comprehensive Income (Rollforward of Total Equity) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Common Stock [Abstract]
Common stock activity, shares			1,000,000
Treasury stock activity, shares			2,000,000	2,000,000
Common Stock, Beginning Balance			$ 2,690,000,000
Capital surplus - Preferred Stock, Beginning Balance			3,590,000,000
Capital surplus - Common Stock, Beginning Balance			12,193,000,000
Retained Earnings, Beginning Balance			20,265,000,000
Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning Balance			834,000,000
Treasury Stock, Beginning Balance			569,000,000
Noncontrolling interests, Beginning Balance			2,762,000,000
Total Equity, Beginning Balance			41,765,000,000	37,246,000,000
Net income	1,123,000,000	546,000,000	2,127,000,000	1,357,000,000
Other comprehensive income (loss), net of tax	(722,000,000)	121,000,000	(789,000,000)	507,000,000
Cash dividends declared [Abstract]
Common			(444,000,000)	(396,000,000)
Preferred			(118,000,000)	(63,000,000)
Redemption of noncontrolling interests			(375,000,000)
Common stock activity			35,000,000	30,000,000
Treasury stock activity			74,000,000	82,000,000
Other			(680,000,000)	(31,000,000)
Common Stock, Ending Balance	2,693,000,000		2,693,000,000
Capital surplus - Preferred Stock, Ending Balance	3,939,000,000		3,939,000,000
Capital surplus - Common Stock, Ending Balance	12,234,000,000		12,234,000,000
Retained Earnings, Ending Balance	21,828,000,000		21,828,000,000
Accumulated Other Comprehensive Income (Loss), Net of Tax, Ending Balance	45,000,000		45,000,000
Treasury Stock, Ending Balance	453,000,000		453,000,000
Noncontrolling interests, Ending Balance	1,655,000,000		1,655,000,000
Total Equity, Ending Balance	41,941,000,000	40,214,000,000	41,941,000,000	40,214,000,000
Par value less than $.5 million at each date	500,000	500,000	500,000	500,000	500,000
Common Stock Per Share Dividends Declared			$ 0.84	$ 0.75
Preferred stock redemption, value	(150,000,000)		(150,000,000)
Preferred stock issuance			496,000,000	1,482,000,000
Series P Preferred Stock [Member]
Cash dividends declared [Abstract]
Preferred Stock, Par or Stated Value Per Share		$ 1		$ 1
Preferred shares issued		15,000		15,000
Series L Preferred Stock [Member]
Cash dividends declared [Abstract]
Preferred shares redeemed			1,500
Preferred Stock, Par or Stated Value Per Share	$ 1		$ 1
Series R Preferred Stock [Member]
Cash dividends declared [Abstract]
Preferred Stock, Par or Stated Value Per Share	$ 1		$ 1
Preferred shares issued	5,000		5,000
Common Stock [Member]
Common Stock [Abstract]
Beginning Balance (in shares)			528,000,000	527,000,000
Ending Balance, (in shares)	531,000,000	529,000,000	531,000,000	529,000,000
Common Stock, Beginning Balance			2,690,000,000	2,683,000,000
Cash dividends declared [Abstract]
Common stock activity			3,000,000	4,000,000
Common Stock, Ending Balance	2,693,000,000	2,687,000,000	2,693,000,000	2,687,000,000
Preferred Stock Including Additional Paid in Capital [Member]
Common Stock [Abstract]
Capital surplus - Preferred Stock, Beginning Balance			3,590,000,000	1,637,000,000
Cash dividends declared [Abstract]
Preferred stock discount accretion			3,000,000	1,000,000
Capital surplus - Preferred Stock, Ending Balance	3,939,000,000	3,120,000,000	3,939,000,000	3,120,000,000
Preferred Stock Including Additional Paid in Capital [Member] | Series P Preferred Stock [Member]
Cash dividends declared [Abstract]
Preferred stock issuance				1,482,000,000
Preferred Stock Including Additional Paid in Capital [Member] | Series L Preferred Stock [Member]
Cash dividends declared [Abstract]
Preferred stock redemption, value	(150,000,000)		(150,000,000)
Preferred Stock Including Additional Paid in Capital [Member] | Series R Preferred Stock [Member]
Cash dividends declared [Abstract]
Preferred stock issuance			496,000,000
Common Stock Including Additional Paid in Capital [Member]
Common Stock [Abstract]
Capital surplus - Common Stock, Beginning Balance			12,193,000,000	12,072,000,000
Cash dividends declared [Abstract]
Common stock activity			32,000,000	26,000,000
Treasury stock activity			(42,000,000)	46,000,000
Other			51,000,000	(46,000,000)
Capital surplus - Common Stock, Ending Balance	12,234,000,000	12,098,000,000	12,234,000,000	12,098,000,000
Retained Earnings [Member]
Common Stock [Abstract]
Retained Earnings, Beginning Balance			20,265,000,000	18,253,000,000
Net income			2,135,000,000	1,356,000,000
Cash dividends declared [Abstract]
Common			(444,000,000)	(396,000,000)
Preferred			(118,000,000)	(63,000,000)
Preferred stock discount accretion			(3,000,000)	(1,000,000)
Redemption of noncontrolling interests			(7,000,000)
Retained Earnings, Ending Balance	21,828,000,000	19,149,000,000	21,828,000,000	19,149,000,000
Accumulated Other Comprehensive Income (Loss) [Member]
Common Stock [Abstract]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning Balance			834,000,000	(105,000,000)
Other comprehensive income (loss), net of tax			(789,000,000)	507,000,000
Cash dividends declared [Abstract]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Ending Balance	45,000,000	402,000,000	45,000,000	402,000,000
Treasury Stock [Member]
Common Stock [Abstract]
Treasury Stock, Beginning Balance			(569,000,000)	(487,000,000)
Cash dividends declared [Abstract]
Treasury stock activity			116,000,000	36,000,000
Treasury Stock, Ending Balance	(453,000,000)	(451,000,000)	(453,000,000)	(451,000,000)
Noncontrolling Interest [Member]
Common Stock [Abstract]
Noncontrolling interests, Beginning Balance			2,762,000,000	3,193,000,000
Net income			(8,000,000)	1,000,000
Cash dividends declared [Abstract]
Redemption of noncontrolling interests			(368,000,000)
Other			(731,000,000)	15,000,000
Noncontrolling interests, Ending Balance	1,655,000,000	3,209,000,000	1,655,000,000	3,209,000,000
Deconsolidation Of Vie Assets	$ 675,000,000		$ 675,000,000